I have my Library Filter open and want to sort my photos based on two different keywords in two columns, so I switch to the keyword option in both columns, though it is only displaying "All (4 keywords)" in the first column and "All (1 keyword)" in the second column. How do I reset this so I have access to sort all of my photos based on all available keywords?
You probably have a folder or collection selected as the current source. The Keywords column shows just the keywords present in the currently selected source. In the Catalog panel on the left, select All Photographs, then you should see all your keywords.